Spatial Atomic Layer Deposition (SALD), an emerging tool for energy materials. Application to new-generation photovoltaic devices and transparent conductive materials

Abstract Materials properties are the keystone of functional devices for energy including energy conversion, harvesting or storage. But to market new energy materials, the development of suitable processing methods allowing affordable prices is needed. Recently, a new approach to atomic layer deposition (ALD) has gained much momentum. This alternative approach is based on separating the precursors in space rather than in time, and has therefore been called Spatial ALD (SALD). With SALD, the purge steps typical of ALD are not needed and thus deposition rates a hundred times faster are achievable. Additionally, SALD can be easily performed at ambient atmosphere, thus it is easier and cheaper to scale up than conventional ALD. This opens the door to widespread industrial application of ALD for the deposition of energy materials for applications including solar energy, energy storage, or smart windows. SALD is presented here and examples of application to photovoltaics and transparent conductive materials are given. We show that SALD is capable of producing high-quality films fully suited for device integration.